We can consolidate OOM checking for both branches by sinking it below
the if.

+ VIR_FREE(user_dir);
+ goto cleanup;
}
- umask(old_umask);

Hmm, on second thought, virFileMakePath is documented as explicitly
using 0777 - umask, but we really do want the new directory to be 0755
if we create it. I think I'll keep the umask modifications intact (if
someone can convince me otherwise, especially if we have a use case for
0775 instead of 0777 or 0755, we can change that in a later patch).

+ if (run_dir)
+ VIR_FREE(run_dir);

Fails 'make syntax-check', due to a useless if before free.

ACK with these changes squashed in, so I pushed. I also added you to
AUTHORS; let me know if I need to update anything there.